In respect to the dentition and facio-maxillary region, the monkey is more similar to man than any other commonly available laboratory animal, and thus is a good model for basic and clinical studies related to the dental sciences. During the last four years the Oral-Facial Growth and Development program project has developed a major primate resource involving a large group of age-known pedigreed Macaca nemestrina and a massive pool of normative growth data for this species. A great deal of new substantive and technical knowledge has been gained and the project now stands on the threshold of entering its most productive period. The future goals of the program project are to continue the basic growth studies over the full developmental period of this species of primate; continue to explore the use of teratogens for producing a primate model of cleft lip and palate; study the influence of normal and abnormal mastication on developmental morphology; and study several specific clinical problems involving tooth replantation, the effects of gingival defects, surgical procedures for superior lip lengthening, and the long-term effects of trauma of the temporomandibular joint.